MOUNT(8)						      System Manager's Manual							  MOUNT(8)

NAME

       mount - mount file systems

SYNOPSIS

       mount [ -adfruvw ] [ -t ufs | external_type ]
       mount [ -dfruvw ] special | node
       mount [ -dfruvw ] [ -o options ] [ -t ufs | external_type ] special node

DESCRIPTION

       The  mount  command  calls the mount(2) system call to prepare and graft a special device on to the file system tree at the point node.	If
       either special or node are not provided, the appropriate information is taken from the fstab(5) file.

       The system maintains a list of currently mounted file systems.  If no arguments are given to mount, this list is printed.

       The options are as follows:

       -a	 Causes everything to be done except for the actual system call.  This option is useful in conjunction with the

       -v	 flag to determine what the mount command is trying to do.

       -f	 Forces the revocation of write access when trying to downgrade a filesystem mount  status  from  read-write  to  read-only.   For
		 2.11BSD this flag is currently not implemented.

       -o	 Options are specified with a -o flag followed by a comma separated string of options.	The following options are available:

		 async	   All	I/O  to  the  file  system should be done asynchronously.  This is a dangerous flag to set, and should not be used
			   unless you are prepared to recreate the file system should your system crash.

		 force	   The same as -f; forces the revocation of write access when trying to downgrade a filesystem	mount  status  from  read-
			   write to read-only.	 This is not (and likely never will be) supported in 2.11BSD.

		 nodev	   Do  not  interpret  character or block special devices on the file system.  This option is useful for a server that has
			   file systems containing special devices for architectures other than its own.

		 noexec    Do not allow execution of any binaries on the mounted file system.  This option is useful for a server  that  has  file
			   systems containing binaries for architectures other than its own.

		 nosuid    Do not allow set-user-identifier or set-group-identifier bits to take effect.

		 rdonly    The same as -r; mount the file system read-only (even the super-user may not write it).

		 sync	   All I/O to the file system should be done synchronously.

		 update    The same as -u; indicate that the status of an already mounted file system should be changed.

		 Any  additional  options  specific  to a filesystem type that is not one of the internally known types (see the -t option) may be
		 passed as a comma separated list; these options are distinguished by a leading - (dash).  Options that take a value are specified
		 using	the  syntax  -option=value.  At present no 2.11BSD mount options use the following form, the example has been retained for
		 illustrative purposes only.  For example, the mount command:

		 mount -t mfs -o nosuid,-N,-s=4000 /dev/dk0b /tmp

		 causes mount to execute the equivalent of:

		 /sbin/mount_mfs -o nosuid -N -s 4000 /dev/dk0b /tmp

       -r	 The file system is to be mounted read-only.  Mount the file system read-only (even the super-user may not write it).  The same as
		 the ``rdonly'' argument to the -o option.

       -t "ufs | external type"
		 The argument following the -t is used to indicate the file system type.  The type ufs is the default.	Ufs is also the only value
		 supported by 2.11BSD other than swap.	Thus the -t will rarely be used.  The -t option can be used to indicate that  the  actions
		 should  only  be taken on filesystems of the specified type.  More than one type may be specified in a comma separated list.  The
		 list of filesystem types can be prefixed with ``no'' to specify the filesystem types for which action should not be  taken.   For
		 example, the mount command:

		 mount -a -t nonfs,mfs

		 mounts all filesystems except those of type NFS and MFS.

		 If  the  type	is  not one of the internally known types, mount will attempt to execute a program in /sbin/mount_XXX where XXX is
		 replaced by the type name.  For example, mfs filesystems are mounted by the program /sbin/mount_mfs.

       -u	 The -u flag indicates that the status of an already mounted file system should be changed.  Any of the  options  discussed  above
		 (the  -o  option)  may  be  changed; also a file system can be changed from read-only to read-write or vice versa.  An attempt to
		 change from read-write to read-only will fail if any files on the filesystem are currently open for writing unless the -f flag is
		 also  specified.   This is currently not implemented in 2.11BSD.  The ability to change the flags (nodev, nosuid, etc) is however
		 supported.  The set of options is determined by first extracting the options for the file  system  from  the  fstab  table,  then
		 applying any options specified by the -o argument, and finally applying the -r or -w option.

       -v	 Verbose mode.

       -w	 The file system object is to be read and write.

FILES

       /etc/fstab
		 file system table

SEE ALSO

       mount(2), fstab(5), umount(8)

BUGS

       It is possible for a corrupted file system to cause a crash.

       mount  and  this  manpage were ported from 4.4BSD-Lite to 2.11BSD to gain the ability to set the various flags such as nodev, nosuid and so
       on.   Multiple filesystem types are not supported and several of the options and flags are not implemented.

HISTORY

       A mount command appeared in Version 6 AT&T UNIX.

4.4 Berkeley Distribution					 November 16, 1996							  MOUNT(8)